...Weather Changes for Interior Northern California this Week...After a weakening Pacific weather system moves through northernCalifornia tonight, a second, colder and wetter system will followWednesday and Thursday. Snow levels are forecast to rapidly lowerbelow the passes Wednesday night, eventually lowering to around2500 feet in the Shasta County mountains to around 3000 feet overthe Sierra. Accumulations from 6 inches to a foot of snow arepossible over the Sierra passes with a dusting to around 3000 feetby Thursday, and several inches over the Shasta County mountainsand the Coastal Range.Travelers over the mountain passes should be prepared for winterdriving conditions Wednesday night through Thursday.High temperatures on Thursday will be much colder than normal withhighs in the upper 50s to lower 60s in the Valley and mainly inthe 30s and 40s in the mountains.A rapid warming trend is forecast for Friday and Saturday withhigh temperatures in the 70s in the Valley and 50s to 60s in themountains.